Andy Wyenandt

All seed used in transplant production, as well as any transplants brought into the greenhouse should be certified ‘clean’ or disease-free.

Seed Treatment

Important diseases such as Bacterial leaf spot of tomato and pepper can cause major problems in transplant production if introduced into the greenhouse. Bacterial leaf spot of tomato and pepper can be seed-borne and infested seed can be a major source of inoculum in the greenhouse and cause problems in the field later in the growing season. As a rule for any crop, any non-certified or untreated seed should be treated, if applicable, with a Clorox treatment, or hot-water seed treatment, or dusted to help minimize bacterial or damping-off diseases. For more information on seed treatments for specific crops please see Table E-14 on page E45 in Section E of the 2014 New Jersey Commercial Vegetable Production Recommendations Guide.

Selected Organic and Conventional Fungicides, Bactericides

An updated table for selected organic and conventional fungicides and bactericides labeled for greenhouse use is available in Section E of the 2014 New Jersey Commercial Vegetable Production Recommendations Guide. The table includes a comprehensive list of fungicides and biological agents approved for greenhouse use. Table E-15 can be found on pages E46-48.

Proper greenhouse sanitation is important for healthy, disease-free vegetable transplant production.

Efforts need to be made to keep transplant production greenhouses free of unnecessary plant debris and weeds which may harbor insect pests and disease. Efforts need to be taken throughout the transplant production season to minimize potential problems.

• All equipment, benches, flats, plug trays and floors should be properly cleaned and then disinfested prior to use.
• Any weeds in or around the greenhouse structure should be removed prior to any production.
• Any transplant brought into the greenhouse from an outside source needs to be certified ‘clean’, as well as, visually inspected for potential insects and diseases once it reaches your location.

Remember, disinfestants, such as Clorox, Green-Shield, or hydrogen dioxide products (Zerotol – for commercial greenhouses, garden centers and Oxidate – commercial greenhouse and field), kill only what they come into direct contact with so thorough coverage and/or soaking is necessary. The labels do not specify time intervals for specific uses, only to state that surfaces be ‘thoroughly wetted’. Therefore, labels need to be followed precisely for different use patterns (i.e., disinfesting flats vs. floors or benches) to ensure proper dilution ratios. Hydrogen dioxide products work best when diluted with water containing little or no organic matter and in water with a neutral pH.